Method of production of engine cylinders



Oct. 12, 1943. F. 'r. IRGENS 5 I METHOD OF PRODUCTION 01"v ENGINE CYLINDERS Filed Aug. 12. 1939 i 5 Sheets-Sheet l INVENTOR FPN/v 7. AeG-EALS Y ATTORNEYQ Oct. 12, 1943. F. T. IRGENS METHOD OF PRODUCTION OF ENGINE CYLINDERS ,3 Sheets-Sheet 2 Filed Aug. 12, 1939 AMrAM' ATTORNEY? 4 F. T. IRGENS Oct. 12, 1943.

METHOD OF PRODUCTION OF ENGINE CYLINDERS Filed'Aug; 12, 1959 3 Sheet-Sheet 3 INVENTOR Patented Oct. 12, 1943 DIETHOD OF CYLIND ritonUc'rIoN F nNenv'n ERS Finn T. Irgens, Wauwatosa, Wis, asslgnor to Outboard, Marine & Manui' acturing Company,

Milwaukee, Wis., a corporation of Delaware Application August 12, 1939', Serial No. 289,746

12 Claims. (Cl. 29-1564) This invention relates to the internal combustion art, and has particular reference to the production of a die cast cylinder block.

Primary objects of the invention are to provide a novel and improved method and construction for the purpose of reducing the expense of manufacture, assuring against corrosion in the cylinder water passages and the passages of a mufller or exhaust manifold requiring cooling; rendering the cooling moreefiective, and particularly rendering it controllable to direct the 0001-.

ing water where needed, and to eliminate dead spots in which circulation has not freely occurred in pastdevices.

More particularly stated, it is one of the object of the invention to maintain a substantially constant rate of flow of coolant through all portions of an internal combustion engine, while permitting extremely eflicient transfer of heat.

From the constructional standpoint, the invention has for its objects a novel and improved means of producing a sleeve-lined cylinder; die cast into a cylinder block, in which the water passage comprises a pre-formed tube wound about the cylinder and cast into the block to eliminate coring, manufacturing operation. In this connection, it is also preferred that the several ports of a twoport or three-port internal combustion engine may be drilled into the block and sleeve, and ports may also be drilled into the block and water tube for water circulation in a manner such as to reduce the expense of manufacture as compared with the coring of the die casting.

Other objects will be apparent to those skilled in the art upon inspection of the following disclosure of the invention.

In the drawings:

Figure 1 is a view in axial section through a single cylinder engine block made in accordance with the invention.

Figure 2 is a view of the block as it appears in side elevation.

Figure3 is a view of the block taken in section on the line 33 of Figure l. a

Figure 4 is a view of the block taken in sectio on the line l-& of Figure 1.

Figure 5 is a plan view of the pro-formed coil used to constitute a water passage.

Figure 6 is a side elevation of the coil.

Figure 7 is a view, partially in side elevation and partially in axial section, through a twocylinder engine block of modified design made in accordance with my invention.

Figure 8 is a side elevation of the block shown in Figure 7.

Figure 9 is a view taken in section on the line 9-9 of Figure 7.

Figure 10 is a view of the block shown in Figure 8 as it appears in'end elevation with a manifold casting applied thereto. Figure 11 is a view taken in section on the line H--ll of Figure 8 and extended to show the manifold casting applied to the block.

Figure 12 is a view of the manifold casting in plan.

Figure 13 is a view of the manifold casting in side elevation.

Like parts are identified by the same reference characters throughout the several views.

' The engine in which the invention is embodied as illustrated in Figures 1 to 6, inclusive, is a single cylinder, two-port engine of the type in which the carburetor or mixing valve is provided with a check valve controlling mixture inlet to the crank case, so that the piston'only controls the trans- I fer of mixture to the combustion cylinder and the and otherwise expedite the release of the burned gases from the cylinder to the exhaust.

The engine in which the invention is embodied as illustrated in Figures 7 to 13, inclusive, is a multi-cylinder engine, which, as shown, has two cylinders of the three-port type, the arrangement being such that the piston controls the admission of combustible mixture to the crank case, and also controls its transfer from the crank case to the combustion cylinder, and also controls the escape of burned gases from the combustion chamber to the exhaust. Those skilled in the art will recognize that both engines illustrated are of the two-cycle type. p

It will be understood that the devices chosen to exemplify the invention are merely illustrative of its many applications.

In-each of my engines the cylinder sleeve and the water passage are preferably pre-formed and cast into place in a die cast cylinder block. The

.single cylinder block I5 is preferably made of some extremely light material, such as an aluminum alloy, in which a wear resistant sleeve I8 of some material such as steel has been cast. Preliminary to the casting operation, a pre-formed helix ll of copper tubing or the like is positioned,

about the sleeve I6 so that upon the conclusion of the die casting operation the tube II will be embedded in the aluminum alloy as a conduit for cooling water. The terminal ends l8 and 19 of the tube I! are brought out to the finished face 20 of the die casting, where they serve to receive the water supply and discharge connections in the usual way.

Cored into the die casting are the transfer port 2! and the exhaust passage 22, best shown in Figures 1 and 4. Upon the conclusion of the die casting operation the cylinder block is placed in a jig, or is otherwise supported, while parallel drills are used at an oblique angle to bore into the block and sleeve to provide the transfer ports 23 and the exhaust ports 24. The angularity at which these holes are bored locates the transfer ports at a lower level with reference to the direction of piston travel than the exhaust ports, thus giving the correct timing.

The completed engine cylinder is extremely light in weight and is manufactured with unusual economy and operates with unusual effectiveness. in that the water passage has no dead spots, but is of uniform cross section throughout, carrying the cooling water exactly where most needed to promote most eflicient cooling, and promoting a very eflicient heat transfer because the highly conductive aluminum alloy is bonded both to the steel sleeve I6 and to the highly conductive helical tube H constituting the water passage.

In the construction shown in Figures '7 to 13. inclusive, the cylinder block 25 is die cast about two cylinder sleeves 26 and a water coil 21, which is not a true helix, but has the peculiar form clearly shown in Figures 7, 9'and 10. In plan, the water coil has something the outline of the link of a chain. In elevation. the runs of pipe comprising its sides are straight and parallel, as shown in Figure '7, the entire pitch being provided at the ends of the coil as shown inFigure 10, and indicated in Figure 9 by the plane in which the coil is intersected in that view. One end of the tube comprising the coil 21 is brought out at the crank case end of the casting, as indicated at 28 in Figures '7, 8 and 10. This is preferably the inlet end. The discharge or return end of the coil 29 is brought out to the finish face 38, as best shown in Figures 8 and 10. Whereas, in the construction shown in Figures 1 to 6, the coil is illustrated as being applied directly about the cylinder sleeve 15, the construction exemplifying the invention in Figures 7 to 11 is such that the coil is spaced slightly from the cylinder sleeve, leaving an intervening film of the die cast metal comprising the block. Either method is satisfactory, and in either instance the die casting bonds the coil and the sleeve for effective heat transfer.

In the two-cylinder engine the transfer port is provided at 3! by a recess cored into the die casting and covered by a closure plate am as indicated in Figure 11. The exhaust passage comprises a recess (-32 cored into the cylinder block within the finish surface 30 and opening to the end of the block, as shown in Figure 10. The inlet manifold comprises another passage within the finish surface 38, as indicated at 33 in Figures 8 and 11. The respective passages 32 and 33 are preferably enlarged by a casting 35 which comprises a muffler and manifold fitting provided internally, with a recess 36 registering with recess 32 and a recess E'i registering with recess 33 of the cylinder block. The latter recess communicates with the carburetor inlet indicated at 38, the carburetor not being shown. The recess 36 constitutes a muffler or expansion chamber and has no outlet except through the opening at the side of the cylinder block, as shown in Figure 10. This part of the manifold fitting is preferably water cooled, andfor this purpose a length of tubing 40 is embedded in the manifold fittin 35, as shown in Figures 11, 12, and 13,- this length of tubing being die cast into the casting 35 and provided with one end II which registers with the outlet end 29 of the cylinder jacket tube 21. For convenience in the die casting op the other end 42 of the tubing is brought out parallel to the end 4 I ,but is seated against an imperforate boss 43 of the cylinder casting which is shown in Figure 8.

The water is brought out at the desired point by boring into the manifold casting 35 at one end to provide a hole 44 which penetrates and intersects the tube 40, as best shown in Figures 12 and 13.

As in the construction first described, this device provides an extremely light weight cylinder block, which, at the same time, is strong and wear resistant by reason of the provision of the sleeve, and which provides the cooling water exactly where needed and assures uniformity of flow without eddy currents by reason of the uniform cross section of the water passage. The several mixture inlet ports 35, transfer ports 45, and exhaust ports 4'! are drilled through the block and the sleeve cast therein by drills which enter through the respective recesses 33, 3| and 32.

I claim:

1. A method of cylinder construction, which comprises pro-forming a cylinder sleeve, positioning said sleeve in a mold, positioning cores in the mold on opposite sides and exteriorly of said sleeve to provide both a transfer passage paralleling said sleeve and a recess opposite said transfer passage, casting metal in said mold exteriorly of said sleeve, withdrawing the cores to expose said passage and recess, and boring at least one hole from said recess completely through the walls of said sleeve and into said passage.

A method of cylinder construction, which comprises pro-forming a cylinder sleeve, positioning said sleeve in a mold, positioning cores in the mold on opposite sides and exteriorly of said sleeve to provide both a transfer passage paralleling said sleeve and a recess opposite said transfer passage, casting metal in said mold about said sleeve, withdrawing the cores to expose said passage and recess, and boring a plurality of holes obliquely from said recess through opposite walls of the cast metal and the sleeve into said passage, whereby to provide a series of ports ofiset axially of said. cylinder sleeve and affording communication between said sleeve and passage and recess, respectively.

3. A method of making a water jacketed light weight cylinder for an internal combustion engine, which method comprises preforming an engine cylinder lining sleeve, preforming a tube to provide access ends and an intermediate tubular jacketing coil of a diameter to telescopically receive the sleeve and of a length to encircle only one end portion of the sleeve, positioning one end portion of the sleeve within the coil, and casting a light low melting point metal as a cylinder block in bonded relation to the sleeve and intermediate coil portions of the tube, exposing said ends.

4. A method of manufacturing a light weight water cooled internal combustion engine cylinder, which comprises preforming an engine cylinder sleeve, preforming a water conducting tube, positioning the tube in encircling relation to the preformed sleeve, and die casting low melting point light weight metal about the sleeve in embedding and bonding relation to the tube, to the portions of the sleevewhich it encircles, and across one end of the sleeve to form a cylinder head.

5. A method of manufacturing an internal combustion engine cylinder, comprising preforming a cylindrical engine cylinder liner sleeve, preforming a tubular coil of an internal diameter to fit over the sleeve and of a length to enclose only a part of the length of the sleeve, locating the coil at one end of the sleeve, and die casting light weight, low melting point inetal to comprise a cylinder block about the sleeve in embedding relation to the coil and bonding the coil to the sleeve.

6. A method of making a light weight cylinder for a two cycle internal combustion engine, which method comprises preforming a sleeve, die casting light weight and low melting point metal about the sleeve while providing passages in such light weight 'metal at opposite sides of the sleeve, at least one of which is a blind passage opening only toward one end of the sleeve, and drilling from the other of said passages into the casting and completely through both sides of the sleeve and the opposite portion of the casting into the blind passage at a point spaced from its opening, whereby to provide ports leading from both of said passages to the interior of the sleeve.

7. A method of making a light weight cylinder for a two cycle internal combustion engine, which method comprises the preforming of the cylinder sleeve open at both ends, the casting of a light weight metal about the sleeve and across one ,end thereof to comprise a cylinder' blockv while forming a blind passage adjacent the sleeve and opening adjacent the open end of the sleeve and extending thence along the sleeve toward the end thereof closed by said casting, and boring at least one hole through the cylinder block from a point opposite said blind passage completely across said sleeve and into said blind passage at a point remote from the open end thereof, whereby to afford a communication port from said passage into the interior of said sleeve.

8. A method of constructing a cylinder block for a two cycle internal combustion engine, said method comprising the preforming of an engine cylinder sleeve, casting a cylinder block about said sleeve while coring into said block a blind transfer passage opening adjacent one end of the sleeve and extending longitudinally of the sleeve toward the other end thereof, and boring transversely of the block and sleeve from a point I opposite said passage a plurality of holes substantially in a common plane to which the axis of said sleeve is oblique, said holes entering said passage to provide cylinder inlet ports offset axially of said sleeve from the points where said holes enter said sleeve, the .holes at said latter points comprising exhaust ports for the engine cylinder.

9. A method of making a cylinder block for a two cycle internal combustion engine, which method comprises pre-forming a sleeve the casting ofQa cylinder block about the sleeve to provide a blind transfer passage, a cylinder bore and an exhaust recess opposite said passage, and theboring of a plurality of holes from the exhaust recess through the block and both sides of the sleeve across the cylinder bore into the blind transfer passage substantially in a common plane to which the axis of said cylinder bore isoblique, wherebyto provide inlet ports from the blind transfer passage into the cylinder bore and axially offset exhaust ports from the cylinder bore to the exhaust recess, eachof said ports having a diameter materially smaller than the diameter of said cylinder bore.

. 10. The method of constructing a light weight cylinder block for a two cycle internal combustion engine, whichmethod comprises prefabricating a ferrous cylinder sleeve, casting light weight low melting point metal about said sleeve and across one end thereof to comprise a cylinder block while coring a blind transfer passage opening adjacent the open end of said sleeve and extending along one side thereof and an exhaust recess at the other side of said sleeve, and the boring of at least one hole materially smaller in diameter than the diameter of said sleeve obliquely from the exhaust recess acrossthe block and the sleeve into said blind passage at an inclination toward the open end of said blind passage, whereby to provide inlet and exhaust ports leading to and from the interior of said sleeve and ofiset axially thereof and sufllciently smaller than said sleeve to leave adequate bearing support for a piston reciprocating sleeve.

11. The method of making a water jacketed light weight cylinder block for a-two cycle internal combustionengine, which method comprises preforming at least one cylinder sleeve,

preiorming a water jacket tube as a coil to flt one the sleeve, said block embedding said coil and' being bonded both to said coil and sleeve, and drilling across said block from the side opposite said passage through both sides of the sleeve and into said passaage at least one hole of materially smaller diameter than the diameter of said sleeve, whereby to provide inlet port means from said passage to said sleeve and opposite exhaust port means from said sleeve.

12. The method of making a water jacketed light weight cylinder block for a two-cycle internal combustion engine, which method comprises pre-forming at least one cylinder sleeve,

pre-forming a water jacket tube as a coil to fit one end portion of said sleeve, exposing other portions thereof, positioning the pre-formed coil about the sleeve end portion to which it is fitted, molding a light weight low melting point metal about the coil and sleeve to comprise a cylinder block; forming along one side portion of the sleeve exposed by said coil a.b1ind transfer passage in said block opening adjacent one end of means from said sleeve, with said inlet and exhaust port means offset axially of said sleeve to the extent that said drilling is oblique.

FINN T. IRGENS. 

